dom/media/VideoTrackList.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "mozilla/dom/VideoTrack.h"
   7 #include "mozilla/dom/VideoTrackList.h"
   8 #include "mozilla/dom/VideoTrackListBinding.h"
   9
  10 namespace mozilla::dom {
  11
  12 JSObject* VideoTrackList::WrapObject(JSContext* aCx,
  13                                      JS::Handle<JSObject*> aGivenProto) {
  14   return VideoTrackList_Binding::Wrap(aCx, this, aGivenProto);
  15 }
  16
  17 VideoTrack* VideoTrackList::operator[](uint32_t aIndex) {
  18   MediaTrack* track = MediaTrackList::operator[](aIndex);
  19   return track->AsVideoTrack();
  20 }
  21
  22 void VideoTrackList::RemoveTrack(const RefPtr<MediaTrack>& aTrack) {
  23   // we need to find the video track before |MediaTrackList::RemoveTrack|. Or
  24   // mSelectedIndex will not be valid. The check of mSelectedIndex == -1
  25   // need to be done after RemoveTrack. Also the call of
  26   // |MediaTrackList::RemoveTrack| is necessary even when mSelectedIndex = -1.
  27   bool found;
  28   VideoTrack* selectedVideoTrack = IndexedGetter(mSelectedIndex, found);
  29   MediaTrackList::RemoveTrack(aTrack);
  30   if (mSelectedIndex == -1) {
  31     // There was no selected track and we don't select another track on removal.
  32     return;
  33   }
  34   MOZ_ASSERT(found, "When mSelectedIndex is set it should point to a track");
  35   MOZ_ASSERT(selectedVideoTrack,
  36              "The mSelectedIndex should be set to video track only");
  37
  38   // Let the caller of RemoveTrack deal with choosing the new selected track if
  39   // it removes the currently-selected track.
  40   if (aTrack == selectedVideoTrack) {
  41     mSelectedIndex = -1;
  42     return;
  43   }
  44
  45   // The removed track was not the selected track and there is a
  46   // currently-selected video track. We need to find the new location of the
  47   // selected track.
  48   for (size_t ix = 0; ix < mTracks.Length(); ix++) {
  49     if (mTracks[ix] == selectedVideoTrack) {
  50       mSelectedIndex = ix;
  51       return;
  52     }
  53   }
  54 }
  55
  56 void VideoTrackList::EmptyTracks() {
  57   mSelectedIndex = -1;
  58   MediaTrackList::EmptyTracks();
  59 }
  60
  61 VideoTrack* VideoTrackList::GetSelectedTrack() {
  62   if (mSelectedIndex < 0 ||
  63       static_cast<size_t>(mSelectedIndex) >= mTracks.Length()) {
  64     return nullptr;
  65   }
  66
  67   return operator[](mSelectedIndex);
  68 }
  69
  70 VideoTrack* VideoTrackList::IndexedGetter(uint32_t aIndex, bool& aFound) {
  71   MediaTrack* track = MediaTrackList::IndexedGetter(aIndex, aFound);
  72   return track ? track->AsVideoTrack() : nullptr;
  73 }
  74
  75 VideoTrack* VideoTrackList::GetTrackById(const nsAString& aId) {
  76   MediaTrack* track = MediaTrackList::GetTrackById(aId);
  77   return track ? track->AsVideoTrack() : nullptr;
  78 }
  79
  80 }  // namespace mozilla::dom